Observation of a Narrow Resonance Formed in e+ e- Annihilation at 9.46-GeV

The Pluto collaboration Berger, Christoph ; Lackas, W. ; Raupach, F. ; et al.
Phys.Lett.B 76 (1978) 243-245, 1978.
Inspire Record 130053 DOI 10.17182/hepdata.27457

An experiment using the PLUTO detector has observed the formation of a narrow, high mass, resonance in e + e − annihilations at the DORIS storage ring. The mass is determined to be 9.46±0.01 GeV which is consistent with that of the Upsilon. The gaussian width σ is observed as 8±1 MeV and is equal to the DORIS energy resolution. This suggests that the resonance is a bound state of a new heavy quark-antiquark pair. An electronic width Γ ee =1.3±0.4 keV was obtained. In standard theoretical models, this favors a quark charge assignment of 1 3 .

1 data table

No description provided.


The Total Hadronic Cross-Section for e+ e- Annihilation Between 3.1-GeV and 4.8-GeV Center-Of-Mass Energy

The PLUTO collaboration Burmester, J. ; Criegee, L. ; Dehne, H.C. ; et al.
Phys.Lett.B 66 (1977) 395-400, 1977.
Inspire Record 110272 DOI 10.17182/hepdata.27583

Using the solenoidal magnetic detector PLUTO, we have measured the total cross section for e + e − annihilation into hadrons. Results are presented for center of mass energies between 3.6 and 4.8 GeV, and in the regions of the J ψ (3.1) and ψ(3.7) resonances. We also present results for the 2 prong cross section in the energy range 3.6 to 4.8 GeV.

2 data tables

No description provided.

NUMBERS MEASURED OFF PUBLISHED FIGURE. RADIATIVE CORRECTIONS HAVE BEEN APPLIED.


Hadron Production by electron-Positron Annihilation at 5-GeV Center-Of-Mass Energy

Tarnopolsky, G. ; Eshelman, J. ; Law, M.E. ; et al.
Phys.Rev.Lett. 32 (1974) 432-435, 1974.
Inspire Record 745 DOI 10.17182/hepdata.21302

We have measured the cross section σ for electron - positron annihilation into three or more hadrons, with at least two charged particles in the final state, at 5 GeV center-of-mass energy. We find a model-independent lower limit of σ>9.1±1.0nb; assuming invariant phase-space production of pions, we calculate the detection efficiency of our detector to be (45 ± 11)%, yielding a cross section σ=21±5nb. The average charged hadron multiplicity is found to be n¯=4.3±0.6.

1 data table

No description provided.


Hadron Production by electron positron annihilation at 4-GeV center-of-mass energy

Litke, A. ; Hanson, G. ; Hofmann, A. ; et al.
Phys.Rev.Lett. 30 (1973) 1189-1192, 1973.
Inspire Record 85252 DOI 10.17182/hepdata.21416

We have measured the total cross section for electron-positron annihilation into three or more hadrons, with at least two charged particles in the final state. The measurement was made at a center-of-mass energy of 4 GeV with a 2π−sr nonmagnetic detector. With 88 events detected, we obtain a model-independent lower limit on the hadron production cross section of 9.6 ± 1.4 nb; a calculation of detection efficiency based on invariant phase-space production of pions leads to a total cross section of 26 ± 6 nb. This cross section is 4.7 ± 1.1 times the theoretical total cross section for e+e−→μ+μ−. The average charged multiplicity is n¯=4.2±0.6.

1 data table

No description provided.